1. Field of the Invention
The present invention relates to the building construction tools, and particularly to a shingle cutter which permits the on-site cutting of roofing shingles using a one-man operated machine.
2. Description of Related Art
A number of mechanical cutters and trimmers for producing fiber glass and asphalt roof shingles in a desired shape have been constructed and marketed, but most roofers have relied on a utility knife for cutting shingles in view of the knife""s portability and simplicity.
Some shingle cutters are designed to produce particular kinds and shapes of shingles that are used in well-defined and specialized circumstances. For example, U.S. Pat. No. 4,951,540, issued to Cross et al., discloses a shingle ridge cap cutter used for cutting uniform sections from roof shingles. This cutter comprises a frame along which a shingle is guided under a manually operated cutter holding two blades with cutting edges positioned downward so that the cut shingle resembles a trapezoid adjoined to a rectangle so that the base of the trapezoid and a side of the rectangle coincide. Similarly, U.S. Pat. No. 5,052,256, issued to Morrissey, discloses a shingle cutting apparatus that produces a trapezoid-on-rectangle shingle used on ridge caps. The Morrissey cutter has grooves in the base into which the blades can fit.
Other patents deal with manufacturing processes that have also been applied to small scale applications. For example, U.S. Pat. No. 5,165,314, issued to Paulson et al., discloses the use of a rotating slitting blade. This devise is used to cut sheets of corrugated paperboard. Similarly, U.S. Pat. No. 5,322,001, issued to Boda, discloses a paper cutter using circular blades.
Several shingle cutters use a pivotal cutting blade. For example, U.S. Pat. No. 5,249,495, issued to Renk, discloses a pivotal cutter blade and anvil upon which the blade is mounted ins cooperation. A fence rotates in the plane of the base, so that angular cuts on a shingle can be made. Similarly, U.S. Pat. No. 5,787,781, issued to Hile, discloses a shingle cutter for cutting a straight even line and has a straight cutting edge pivotally mounted on a side and corner of the base. There is a bearing and lock nut disposed on a threaded rod and this combination keeps the blade tight against a support member recessed in the base. The base can be attached to legs.
U.S. Pat. No. 5,644,963, issued to Fountas, discloses a guide with no cutting edge.
It is apparent that no device other than a utility knife has gained wide-spread popularity for cutting and trimming shingles at the spot where the shingles are to be installed. Most of the devices are too cumbersome to be relocated on the roof or they are used only to perform specialized tasks. Recent changes in the manufacture of shingles from a single layer to a multi-layer shingle has made the hand cutting of shingles even more difficult than in the past further necessitating a cutting device which is efficient, easily portable, usable in place on a roof, and easily operated by a workman located on a roof slope.
None of the above inventions and patents, taken either singly, or in combination, is seen to describe the instant invention as claimed.
The shingle cutter according to the present invention is used to cut a shingle to produce a shingle having a desired size and shape. The shingle cutter is portable and can be temporarily attached to and used on a roof. The power for cutting results from the housing of the cutting wheel being manually drawn back towards the operator.
The shingle cutter has a structural base attached to two end upright pieces that support a rectangular rack or bar, upon which a cutting wheel housing moves in a sliding manner. In one embodiment, the teeth of the bottom edge of the rack engage the gear teeth of a pinion, which in turn engage a circle of gear teeth fixed with and concentric with the cutting wheel. In another embodiment, the cutting block is supported by a rectangular guide bar with no teeth on its bottom edge. The cutting wheel is rotatably mounted on an axle disposed in a cutting block housing which is slidable along the bar. In both embodiments, the cutting block housing slides along the rectangular bar on four rollers whose axes are perpendicular to and are held rigidly by the two cutting block housing plates.
Accordingly, it is a principal object of the invention to provide a device for producing an efficient and clean cut edge on roof shingles in order to produce custom cut roof shingles.
It is another object of the invention to provide a convenient and easy to operate mechanism for cutting shingles.
It is a further object of the invention to provide a shingle cutting mechanism that is transportable from job site to job site and from ground level to roof top of the building where roof work is being performed. The shingle cutter of the present invention can be temporarily attached to the roof by a slotted mounting tab.
Still another object of the invention is to provide a device for cutting shingles to produce a variety of shapes for a variety of roofing conditions. Another object of the invention is to accommodate recent changes in the manufacture of shingles from a single layer to a multiple layer. This has made the cutting of shingles more difficult. This change has created a need for a more efficient and easier method of cutting shingles.
It is an object of the invention to provide improved elements and arrangements thereof in an apparatus for the purposes described which is inexpensive, dependable and fully effective in accomplishing its intended purposes.
These and other objects of the present invention will become readily apparent upon further review of the following specification and drawings.